* I implement an improved positioning of dropdown window of Combobox and EditCombo when it runs out of screen space. It also handles resizing if the dropdown is bigger that the screen is high.

* Started refactoring the ComboBox and EditComboBox. There was just to much code duplication. I am still busy with it, but please test and let me know if I broke something.

1 files changed, 31 insertions, 121 deletions

diff --git a/src/gui/gui_editcombo.pas b/src/gui/gui_editcombo.pas
index a1d8a343..b6bfb6c3 100644
--- a/src/gui/gui_editcombo.pas
+++ b/src/gui/gui_editcombo.pas
@@ -57,34 +57,26 @@ uses
   gfx_widget,
   gfxbase,
   fpgfx,
-  gfx_popupwindow;
+  gfx_popupwindow,
+  gui_combobox;
 
 type
   TAllowNew = (anNo, anYes, anAsk);
 
 
-  TfpgAbstractEditCombo = class(TfpgWidget)
+  TfpgAbstractEditCombo = class(TfpgBaseComboBox)
   private
     FAutoCompletion: Boolean;
     FAutoDropDown: Boolean;
     FAllowNew: TAllowNew;
-    FDropDownCount: integer;
     FText: string;
     FSelectedItem: integer;
     FMaxLength: integer;
-    FFocusItem: integer;
-    FFont: TfpgFont;
     FInternalBtnRect: TfpgRect;
-    FItems: TStringList;
-    FOnChange: TNotifyEvent;
     FNewItem: boolean;
-    function    GetFontDesc: string;
     procedure   SetAllowNew(const AValue: TAllowNew);
-    procedure   SetDropDownCount(const AValue: integer);
     procedure   InternalBtnClick(Sender: TObject);
     procedure   InternalListBoxSelect(Sender: TObject);
-    procedure   SetFocusItem(const AValue: integer);
-    procedure   SetFontDesc(const AValue: string);
     procedure   CalculateInternalButtonRect;
     procedure   MsgPopupClose(var msg: TfpgMessageRec); message FPGM_POPUPCLOSE;
   protected
@@ -95,7 +87,7 @@ type
     FSelStart: integer;
     FSelOffset: integer;
     FCursorPos: integer;
-    procedure   DoDropDown; virtual;
+    procedure   DoDropDown; override;
     function    GetText: string; virtual;
     function    HasText: boolean; virtual;
     procedure   SetText(const AValue: string); virtual;
@@ -108,24 +100,16 @@ type
     procedure   HandleResize(awidth, aheight: TfpgCoord); override;
     procedure   HandlePaint; override;
     procedure   PaintInternalButton; virtual;
-    property    DropDownCount: integer read FDropDownCount write SetDropDownCount default 8;
-    // property is 0-based
-    property    Items: TStringList read FItems;    {$Note Make this read/write}
-    // property is 1-based
-    property    FocusItem: integer read FFocusItem write SetFocusItem;
     property    AutoCompletion: Boolean read FAutocompletion write FAutoCompletion default False;
     property    AutoDropDown: Boolean read FAutoDropDown write FAutoDropDown default False;
     property    AllowNew: TAllowNew read FAllowNew write SetAllowNew default anNo;
     property    BackgroundColor: TfpgColor read FBackgroundColor write SetBackgroundColor default clBoxColor;
     property    TextColor: TfpgColor read FTextColor write SetTextColor default clText1;
-    property    FontDesc: string read GetFontDesc write SetFontDesc;
-    property    OnChange: TNotifyEvent read FOnChange write FOnChange;
     property    Text: string read GetText write SetText;
   public
     constructor Create(AOwner: TComponent); override;
     destructor  Destroy; override;
     procedure   Update;
-    property    Font: TfpgFont read FFont;
     property    NewText: boolean read FNewItem;
     property    OnKeyPress;
   end;
@@ -255,8 +239,8 @@ begin
   Result.Top       := y;
   Result.Width     := w;
   Result.Focusable := True;
-  if h < TfpgEditCombo(Result).FFont.Height + 6 then
-    Result.Height:= TfpgEditCombo(Result).FFont.Height + 6
+  if h < TfpgEditCombo(Result).Font.Height + 6 then
+    Result.Height:= TfpgEditCombo(Result).Font.Height + 6
   else
     Result.Height:= h;
 
@@ -266,24 +250,12 @@ end;
 
 { TfpgAbstractEditCombo }
 
-procedure TfpgAbstractEditCombo.SetDropDownCount(const AValue: integer);
-begin
-  if FDropDownCount = AValue then
-    Exit;
-  FDropDownCount := AValue;
-end;
-
 procedure TfpgAbstractEditCombo.SetAllowNew(const AValue: TAllowNew);
 begin
   if FAllowNew <> AValue then
     FAllowNew:= AValue;
 end;
 
-function TfpgAbstractEditCombo.GetFontDesc: string;
-begin
-  Result := FFont.FontDesc;
-end;
-
 function TfpgAbstractEditCombo.GetText: string;
 var
   i: integer;
@@ -351,8 +323,8 @@ end;
 procedure TfpgAbstractEditCombo.DoDropDown;
 var
   ddw: TDropDownWindow;
-  rowcount, i, t: integer;
-  theparent: TfpgWidget;
+  rowcount, i: integer;
+  r: TfpgRect;
 begin
   if (not Assigned(FDropDown)) or (not FDropDown.HasHandle) then
   begin
@@ -376,8 +348,8 @@ begin
 
     // adjust the height of the dropdown
     rowcount := ddw.ListBox.Items.Count;
-    if rowcount > FDropDownCount then
-      rowcount := FDropDownCount;
+    if rowcount > DropDownCount then
+      rowcount := DropDownCount;
     if rowcount < 1 then
       rowcount := 1;
     ddw.Height := (ddw.ListBox.RowHeight * rowcount) + 4;
@@ -387,30 +359,9 @@ begin
     ddw.ListBox.FocusItem := FFocusItem;
 
     ddw.DontCloseWidget := self;  // now we can control when the popup window closes
-    theparent := Self;
-    t:= 0;
-    repeat
-      t := t + theparent.Top;
-      theparent:= theparent.Parent;
-    until theparent is TfpgForm;
-    if (t + Height + ddw.Height) > theparent.Height then
-      if t > ddw.Height then
-        ddw.ShowAt(Parent, Left, Top - ddw.Height)         // drop the list above the combo
-      else
-      begin
-        while (t + Height + ddw.Height) > theparent.Height do
-        begin
-          FDropDownCount:= FDropDownCount - 1;
-          if rowcount > FDropDownCount then
-            rowcount:= FDropDownCount;
-          ddw.Height := (ddw.ListBox.RowHeight * rowcount) + 4;
-          ddw.ListBox.Height := ddw.Height;
-        end;
-        ddw.ShowAt(Parent, Left, t + Height);           // drop a reduced list below the combo
-      end
-    else
-      ddw.ShowAt(Parent, Left, Top + Height);           // drop the list below the combo
-//    ddw.ListBox.SetFocus;
+    r := GetDropDownPos(Parent, self, ddw);
+    ddw.Height := r.Height;
+    ddw.ShowAt(Parent, r.Left, r.Top);
   end
   else
   begin
@@ -435,7 +386,7 @@ begin
     // Items is 0-based and FocusItem is 1-based
     if Items[i]= TDropDownWindow(FDropDown).ListBox.Items[TDropDownWindow(FDropDown).ListBox.FocusItem-1] then
     begin
-      FFocusItem := i+1;
+      FocusItem := i+1;
       Break;
     end;
   end;
@@ -443,35 +394,6 @@ begin
 
   if HasHandle then
     Repaint;
-  if Assigned(FOnChange) then
-    FOnChange(self);
-end;
-
-{ Focusitem is 1 based and NOT 0 based like the Delphi ItemIndex property.
-  So at startup, FocusItem = 0 which means nothing is selected. If
-  FocusItem = 1 it means the first item is selected etc. }
-procedure TfpgAbstractEditCombo.SetFocusItem(const AValue: integer);
-begin
-  if FFocusItem = AValue then
-    Exit; //==>
-  FFocusItem := AValue;
-
-  // do some limit check corrections
-  if FFocusItem < 0 then
-    FFocusItem := 0   // nothing is selected
-  else if FFocusItem > FItems.Count then
-    FFocusItem := FItems.Count;
-
-  RePaint;
-end;
-
-procedure TfpgAbstractEditCombo.SetFontDesc(const AValue: string);
-begin
-  FFont.Free;
-  FFont := fpgGetFont(AValue);
-  if Height < FFont.Height + 6 then
-    Height := FFont.Height + 6;
-  RePaint;
 end;
 
 procedure TfpgAbstractEditCombo.SetText(const AValue: string);
@@ -479,19 +401,19 @@ var
   i: integer;
 begin
   if AValue = '' then
-    SetFocusItem(0)  // nothing selected
+    FocusItem := 0  // nothing selected
   else
   begin
-    for i := 0 to FItems.Count - 1 do
+    for i := 0 to Items.Count - 1 do
     begin
-      if SameText(UTF8Copy(FItems.Strings[i], 1, UTF8Length(AVAlue)), AValue) then
+      if SameText(UTF8Copy(Items.Strings[i], 1, UTF8Length(AVAlue)), AValue) then
       begin
-        SetFocusItem(i+1); // our FocusItem is 1-based. TStringList is 0-based.
+        FocusItem := i+1; // our FocusItem is 1-based. TStringList is 0-based.
         Exit;
       end;
     end;
     // if we get here, we didn't find a match
-    SetFocusItem(0);
+    FocusItem := 0;
   end;
 end;
 
@@ -544,8 +466,7 @@ begin
   end;
 
   if prevval <> FText then
-    if Assigned(FOnChange) then
-      FOnChange(self);
+    DoOnChange;
 
   if consumed then
     RePaint
@@ -566,7 +487,7 @@ begin
     keyBackSpace:
         begin
           if HasText then
-            FocusItem:= 0;
+            FocusItem := 0;
           if FCursorPos > 0 then
           begin
             UTF8Delete(FText, FCursorPos, 1);
@@ -578,8 +499,8 @@ begin
     keyDelete:
         begin
           if HasText then
-            FocusItem:= 0;
-          FSelectedItem:= -2;      // detects delete has been pressed
+            FocusItem := 0;
+          FSelectedItem := -2;      // detects delete has been pressed
           hasChanged := True;
         end;
 
@@ -608,12 +529,9 @@ begin
 
   if consumed then
     RePaint;
-//  else
-//    inherited;
 
   if hasChanged then
-    if Assigned(FOnChange) then
-      FOnChange(self);
+    DoOnChange;
   inherited HandleKeyPress(keycode, shiftstate, consumed);
 end;
 
@@ -678,10 +596,10 @@ var
       st  := st + len;
       len := -len;
     end;
-    tw  := FFont.TextWidth(UTF8Copy(Items[FSelectedItem], 1, st));
-    tw2 := FFont.TextWidth(UTF8Copy(Items[FSelectedItem], 1, st + len));
+    tw  := Font.TextWidth(UTF8Copy(Items[FSelectedItem], 1, st));
+    tw2 := Font.TextWidth(UTF8Copy(Items[FSelectedItem], 1, st + len));
     Canvas.XORFillRectangle(fpgColorToRGB(lcolor) xor $FFFFFF,
-      -FDrawOffset + FMargin + tw, 3, tw2 - tw, FFont.Height);
+      -FDrawOffset + FMargin + tw, 3, tw2 - tw, Font.Height);
   end;
 
 begin
@@ -746,7 +664,7 @@ begin
       if Texte <> '' then
         if FSelectedItem > -1 then
         begin
-          FSelOffset:= FFont.TextWidth(UTF8Copy(Items[FSelectedItem], UTF8Length(FText) + 1,
+          FSelOffset:= Font.TextWidth(UTF8Copy(Items[FSelectedItem], UTF8Length(FText) + 1,
             UTF8Length(Items[FSelectedItem]) - UTF8Length(FText)));
           fpgStyle.DrawString(Canvas, FMargin+1, FMargin, FText + UTF8Copy(Items[FSelectedItem],
             UTF8Length(FText) + 1, UTF8Length(Items[FSelectedItem]) - UTF8Length(FText)), Enabled);
@@ -766,8 +684,8 @@ begin
 
       // drawing cursor
       FCursorPos:= UTF8Length(FText);
-      tw := FFont.TextWidth(UTF8Copy(FText, 1, FCursorPos));
-      fpgCaret.SetCaret(Canvas, -FDrawOffset + FMargin + tw, 3, fpgCaret.Width, FFont.Height);
+      tw := Font.TextWidth(UTF8Copy(FText, 1, FCursorPos));
+      fpgCaret.SetCaret(Canvas, -FDrawOffset + FMargin + tw, 3, fpgCaret.Width, Font.Height);
     end
     else
       fpgCaret.UnSetCaret(Canvas);
@@ -810,13 +728,10 @@ end;
 constructor TfpgAbstractEditCombo.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
-  FFont             := fpgGetFont('#List');
   FBackgroundColor  := clBoxColor;
   FTextColor        := Parent.TextColor;
-  FDropDownCount    := 8;
   FWidth            := 120;
-  FHeight           := FFont.Height + 6;
-  FFocusItem        := 0; // nothing is selected
+  FHeight           := Font.Height + 6;
   FMargin           := 3;
   FFocusable        := True;
   FBtnPressed       := False;
@@ -831,17 +746,12 @@ begin
   FSelectedItem     := -1;       // to allow typing if list is empty
   FNewItem          := False;
 
-  FItems  := TStringList.Create;
   CalculateInternalButtonRect;
-
-  FOnChange := nil;
 end;
 
 destructor TfpgAbstractEditCombo.Destroy;
 begin
   FDropDown.Free;
-  FItems.Free;
-  FFont.Free;
   inherited Destroy;
 end;